fix(run): switch node-pty to @lydell/node-pty for the plugin's --ignore-scripts install path

node-pty ships prebuilt binaries for darwin/win32 only — on Linux it
needs a native build via its install script. The plugin's
--ignore-scripts install (scripts/plugin-bootstrap.js, deliberately
skipped to avoid requiring a build toolchain) silently left node-pty
unusable: server/lib/pty-attach.js's require() threw
"Cannot find module './prebuilds/linux-x64//pty.node'" the moment a
terminal was attached, leaving TerminalView permanently blank with no
visible error.

@lydell/node-pty is an API-compatible fork that ships each platform's
binary as a regular optionalDependency instead of a postinstall build
step, so a plain --ignore-scripts install resolves a working native
binding on Linux with no compiler needed. Verified by installing with
the exact `npm install --omit=dev --ignore-scripts` invocation the
plugin bootstrap uses and confirming require() succeeds.

server/lib/pty-attach.js

@@ -1,6 +1,6 @@
 /**
  * @file pty-attach.js
- * @description Bridges one WebSocket connection to a `node-pty`-backed
+ * @description Bridges one WebSocket connection to an `@lydell/node-pty`-backed
  * `tmux attach-session` process. Binary WS frames carry raw PTY bytes in
  * both directions; text WS frames carry small JSON control messages
  * (`resize`, and an outbound `exit` sent once when the pane process/tmux
@@ -98,7 +98,15 @@ function attach(ws, runId, { cols, rows }) {
 }
 
 // Real spawn implementation — lazy-required so unit tests never load the
-// native node-pty addon unless they explicitly opt in.
-__setSpawnImpl((...args) => require("node-pty").spawn(...args));
+// native PTY addon unless they explicitly opt in. Uses @lydell/node-pty (a
+// drop-in-API-compatible fork of node-pty) rather than node-pty itself:
+// node-pty ships prebuilt binaries for darwin/win32 only, so on Linux it
+// needs a native build via its install script — but the plugin install path
+// runs `npm install --ignore-scripts` deliberately (see plugin-bootstrap.js)
+// to avoid requiring a build toolchain on the user's machine. @lydell/node-pty
+// instead ships the platform binary as a regular optionalDependency
+// (@lydell/node-pty-linux-x64 etc.), so a plain --ignore-scripts install still
+// resolves a working native binding with no compiler needed.
+__setSpawnImpl((...args) => require("@lydell/node-pty").spawn(...args));
 
 module.exports = { attach, validateRunId, __setSpawnImpl };